Game Center change account?

I am totally new to ios and apple, so this is a newbie question :)

Is there any way to change the Game Center account that is used in my game on my phone? Either from within my app or someway else?
The reason I ask is because the Leaderboard needs scores submitted from two accounts before they will show, and I only have one device.

You should just be able to log out of Game Center using the Game Center app and set up a new account (you'll need another email to setup a new Apple ID)

Thanks, that was easy :)